Deuteronomy 32:28

for they are a people lost to good counsel and void of understanding.

For they are a nation lacking counsel The enemies of Israel are the referred-to nation. The word lacking, a participle in the construct case (hence the pattaḥ under the vet), here serves as an adjective. It is well known that lacking is an intransitive verb; the word counsel simply explains that which they are lacking. Compare “withered of her leaves” [Isaiah 1: 30]. See also “lost from the way” [Psalms 2: 12], where the construct case is predicated on the word “way”. Accordingly, the translator who rendered “they have lost counsel”, translated wisely.

FOR THEY ARE A NATION VOID OF COUNSEL. [This verse and] the entire section [further on] refers to the aforementioned enemy, according to the words of Rabbi Nechemyah. 322. And, so too, the verse, For their Rock is not as our rock is to be understood as the words of the enemy. Scripture thus states, the enemy should have considered and understood that what was done with Israel had been brought about by G-d because of their sin, and from it they should have realized their own ultimate punishment, for He would do the same to all the nations since they rebel against G-d more than does Israel. They should have been wise and said: “How should one pursue a thousand from Israel except their Rock had given them over. For their Rock is powerful and possesses the capability to help and save more than does our rock, and our enemies [i.e., the Israelites] were ‘pelilim’ (judges) over us originally to execute judgments upon us as they wished. And now, why do a thousand [of the Israelites] flee from before us at the shout of one man, except that their mighty Rock gave them over and sent a faintness into their heart and they fell when there was no pursuer.”, Verse 37. The term ‘pelilim’ (judges) is associated with the expressions: that ‘pilalt’ (thou hast given judgment) for thy sisters; Then stood up Phinehas ‘vayephaleil’ (and wrought judgment).

כי גוי אובד עצות, the word גוי refers to the gentile nations here saying of the Jews that they are totally devoid of direction;

the construction ovad is similar to mispad in מספד תמרורים in Jeremiah 6,26, where instead of misped we find mispad, just as here we find ovad instead of oved. Genesis 30,37 makal instead of makel, is another example of such a construction. The reason for the patach instead of the tzeyreh is that in each instance listed the noun is in a construct mode. A fourth example of such a construction is found in Leviticus 27,32 ma-assar bakar vatzon, instead of ma-asser bakar vatzon.

כי גוי אובד עצות המה, Moses is quoting the gentiles’ assessment of the Jewish people at that point.

כי גוי אובד עצות המה, “for they are a nation void of sense;” this is a reference to the nation into whose hands I will deliver them. They are devoid of sense, so how could they have succeeded in wiping out My people?.